Assisting devices for motor vehicles have a high potential for the improvement of traffic safety, driving comfort and economy of resources. Therefore, increasingly assisting systems are used in modern motor vehicles, which support the driver in driving. Here, it is differentiated between passive assisting systems and technologies actively intervening into the driver process such as e.g. ESP (Electronic Stability Program) or lane departure warnings. Further driver assistance systems supporting the control of the vehicle are ABS (Anti-lock Brake System), TCS (traction control system) or EDS (Electronic Differential Lock).
For increasing the driving comfort navigation systems are used as driver assisting systems. The driver is relieved here by displaying and/or announcing by localization via GPS (Global Positioning System) the necessary turns until the set target point. In this way, a navigation system integrated into a motor vehicle can release driving recommendations, if a destination has been entered and/or programmed and/or stored before into the navigation system. Usually, navigation systems output the route guidances calculated by the navigation computer in visual and/or acoustic manner. Guidance instructions are output in particular when the vehicle approaches decision points, thus in particular intersections or the like. Typical guidance instructions output by the navigation system like e.g. “turn left after 50 meters” are based on distance values.
The vehicle driver has the problem that he must estimate distances exactly and that he must identify an intersection or the like correctly. Mainly in the peak hours in city traffic, at unclear intersections as well as with multi-lane roads the assistance usual with navigation systems cannot be sufficient. Whereas during a cross-country travel with few intersections the destination can be reached without any problems, in particular in case of cities, which can have many intersections or side roads at a narrow space, following of the route guidance will be possible only with increased concentration of the vehicle driver. Possible inattentiveness or misunderstood instructions can lead to detours or unexpected driving behavior, such as sudden deceleration based on too late or too early turning. Above all, the acoustic announcements can be misunderstood, since the announcements for the individual driver are reported too late or too early. Furthermore, in particular at the beginning of the use of a navigation system the acoustic as well as the visual route guidance can be misunderstood by the driver, if the navigation systems differ depending upon the manufacturer or version.